MIL-DTL-26518C
4.7.5 Maintenance aging (see 3.6.4). Each contact shall be inserted, removed, and reinserted using applicable insertion and
removal tools. The connector shall be mated and unmated 10 times and at least 10 of the contacts in both plugs and receptacles
shall be removed and inserted 9 times, using applicable insertion and removal tools. The force measurements required by 4.7.6 shall
be made on the third insertion of 5 contacts of each of the connectors. The purpose of the procedure is to provide accelerated
maintenance aging of the contact, contact locking mechanism, and sealing provisions prior to environmental testing.
4.7.6 Contact insertion force (see 3.6.5). During this test the sealing members shall be relaxed. The force required to push the
contacts into their normal position within the insert, using the applicable insertion tool, shall be measured (see 4.7.5).
4.7.7 Thermal shock (see 3.6.6). The wired, mated connectors shall be subjected to 5 continuous cycles of temperature change.
The two temperature extremes specified in table III shall form the limits the cycle. The first exposure shall be from room temperature
to the lowest extreme. The connectors shall be maintained at each extreme for a period of 30 +5, -0 minutes in each cycle. The
connectors shall be transferred from one chamber to the other for the temperature chamber. The time of exposure at room
temperature shall not exceed 2 minutes during each transfer. Exposure to low temperature, then high, shall form one cycle. During
the last high temperature exposure the insulation resistance test of 4.7.14.1 may be conducted. Upon completion of the last cycle 3
the connectors shall be returned to room ambient conditions for inspection and additional specified tests.
4.7.8 Dielectric withstanding voltage (see 3.6.7).
4.7.8.1 Dielectric withstanding voltage (sea level) (see 3.6.7.1). Mated and unmated connectors shall be tested in accordance with
MIL-STD-202, method 301. Test voltages, as shown in table X, shall be applied between the closest 3 pairs of contacts and also
between the shell and the 3 contacts closest to the shell. Voltage potentials listed for shielded contacts in table X are between inner
conductor and shield, and closest adjacent shields to shell and shell.
4.7.8.2 Dielectric withstanding voltage (altitude) See 3.6.7.2). The connectors shall be placed in a suitable chamber at room
temperature and tested at 20,000 foot intervals, starting at 10,000 feet and concluding at 110,000 feet. The test, for both mated and
unmated connectors, shall be in accordance with MI-STD-202, method 301. Test voltages, as shown in table X, shall be applied
between the closest 3 pairs of contacts as well as between the shell and the 3 contacts closest to the shell. Voltage potentials listed
in table X for shielded contacts shall be tested between inner conductor and shield and between shield and closest adjacent contact,
and closest adjacent shields to shell and shell.
TABLE X. Dielectric withstanding test voltages (AC-rms).
Unmated
Mated
Standard
Shielded 1/
Style P
Shielded 1/
Style S
Shielded 1/
Altitude
contact
contact
contact
voltages
voltages
contact
feet (Km)
Sea level
1500
1000
1500
1000
1500
1000
10,000 (3.05)
1250
825
1250
825
1250
1000
30,000 (9.14)
750
500
700
500
1000
1000
50,000 (15.24)
500
325
450
325
1000
1000
70,000 (21.34)
350
200
275
200
1000
1000
90,000 (27.43)
250
200
200
200
1000
1000
110,000 (33.53)
250
200
200
200
1000
1000
1/ Voltage potential between inner conductor and shield.
4.7.9 Fluid Immersion (see 3.6.8). The unmated connectors shall be immersed in aviation lubricating oil in accordance
MIL-PRF-23699 for 20 hours (samples 7 and 8.). Upon removal from the fluid, the unmated connectors shall remain in free air at
room temperature for 1 hour. The connectors shall then be mated and subjected to the high potential test specified in 4.7.8.1.
4.7.10 Vibration (see 3.6.9). The connector assembly shall be mounted as specified herein and vibrated in accordance with
MIL-STD-202, method 2O4, condition B. In addition, the vibration shall be conducted at a low temperature ambient -55°C and high
ambient 200°C. All contacts shall be wired in series with at least 100 milliamperes of current allowed to flow. A suitable instrument
shall be employed to monitor the current flow and to indicate any discontinuity of contact or interruption of current flow. Duration of
vibration at extreme temperatures shall be 25 percent of the duration specified for the standard temperature condition. The following
shall apply:
Connector mounting - The vibration mounting shall be in accordance with figure 2 except as noted
herein. The plug and receptacle shall be mounted on separate adapter plate, using the connector's
normal mounting provisions and suitable hardware. The adapter plate for the plug shall be attached to
the mounting bracket. The adapter plate for the receptacle shall be subsequently attached to the plug
adapter plate in a manner simulating the normal mated condition in the aircraft.
13
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business